Printing plate and method of manufacturing



July 3, 1951 T. REss PRINTING PLATE AND umnon 0F muumcmmc 3 Sheets-Sheet 1 Filed Jan. 25, 1949 INVENTOR. BY Thomas 1. Bess ,%fl, r MM.

y 3,1951 v T. I. RESS 2,558,877 PRINTING PLATE AND METHOD OF MANUFACTURING Filed Jam 25, 1949 3 Sheets-S eet 2 IN V EN TOR.

T/zmzas 1. Bass dig/s T. I. RESS PRINTING PLATE AND METHOD OF MANUFACTURING July 3, 1951 3 Sheets-Sheet 3 Filed Jan. 25, 1949 Patented July 3, 1951 PRINTING PLATE AND METHOD OF MANUFACTURING Thomas. I. Ress, Chicago, Ill., assignor to The Pioneer Electric and Research Corp., Forest Park, 111., a corporation of Illinois Application January 25, 1949, Serial No. 72,623 4 Claims. (Cl. 101-4011) This invention relates to thin plastic printing plates and a method of making such plates, and it is an object of the invention to provide an improved printing plate and an improved method of manufacturing.

To facilitate the handling of charge accounts, department stores and other places of business have made up individual charge plates or printing plates of metal for each customer. When such customer makes a purchase, he presents his charge plate which identifies him and makes it unnecessary for the clerk to call a central dcpartment to determine if the purchaser has a charge'account. Furthermore, the printing or charge plate is placed in a printer along with the sales slip and an imprint is made thereon of the information on the plate which usually includes a customers name, address, and account number.

Such prior plates, while small, include rims for stiffening purposes so that they are relatively bulky, and it is not .desirable to place them in mens billfolds, for example. Consequently, men usually carry them loose in coat pockets with the attendant possibility of loss or inconvenience in I having to look for them. Carrying such plates in billfolds may result in their becoming bent or distorted so that they are not usable in the printing machine. Accordingly, it is a further object of the invention to provide a printing plate which is flexible and occupies small space.

It is a further object of the invention to provide an improved printing plate of the character described which is economical to manufacture.

It is a further object of the invention to provide an improved plate of the character indicated having clear and sharply defined characters thereon.

It is a further object of the invention to provide an improved method for forming printing plates of the character described having clear and sharp characters thereon.

In carrying out the invention in one form, a pair of fiat, metallic members are assembled one on top of the other, which assembly is then passed between a pair of rolls having corresponding male and female characters arranged thereon. Thereafter the metallic members are reversed in relative positions, a thermoplastic blank is placed therebetween, and heat and pressure are applied thereto for causing the thermoplastic material to flow into the spaces defined by the characters. This method forms a plastic printing plate comprising a substantially flat, flexible plastic member having characters projecting upwardly therefrom on one side.

For a more complete understanding of the in- 2 vention, reference should be had to the accompanying drawings in which:

Figure 1 is a perspective view of a plate embodying the invention;

Fig. 2 is a perspective view diagrammatically indicating apparatus for making printing plate dies;

Fig. 3 is a sectional view of the rolls for forming the dies with the completed dies therebetween, the various parts being separated for clarity;

Fig. 4 is a perspective view of the top surface of one die;

Fig. 5 is a perspective view face of the other die;

Fig. 6 is a perspective view of the dies and material to be formed in relative positions;

Fig. 7 is a side view, partially in section, of a fixture for holding the assembled dies and mate rial to be formed;

Fig. 8 is a view, partially in perspective, of the fixture of Fig. 7 in open position, and

Fig. 9 is an elevational view of heating and pressure apparatus with the fixture of Fig. 7 therein and in section.

Referring to Fig. 1 of the drawings, a printing plate I0 formed by the method of the invention is shown.

Printing plate I0 comprises .a flat piece of thermoplastic material having any desired dimensions upon which a suitable series of characters I I have been formed, the characters, for example, giving the name, street address, city, and account number of any particular individual. It will be understood that such information is only by way of example, and any other information may be embodied in the characters. The plate Ill may be made relatively thin so that it is flexible and occupies relatively little space. However, it may have suflicient resilience so that even though it is deformed it will spring back to its normal fiat character.

The plate may be made of any suitable thermoplastic material, such for example as cellulose acetate in any color.

If desired, suitable notches [2 may be placed around the periphery of the plate in order that it may be properly oriented in a printing apparatus. I

The characters H are sharply defined letters at the top of raised portions 20. Accordingly, the letters are not prevented by the surrounding material from making a sharp imprint on sales slips, for example.

In the remaining figures, the process of forming the plastic printing plate is shown. Referring printin of the bottom surto Figs. 2 and 3, there is shown a pair of mils I3 and I4 held in operative relationship relative to each other by shafts and bearings, not shown. Roll I3 has indentations 23 formed inwardly from its outer surface with letters I6 corresponding to the series of characters II on the printing plate at the top of the indentations. The indentations correspond to the raised portions 20. Likewise, roll I4 has raised portions 22 formed thereon outwardly from its surface with letters I6, also corresponding to the series of characters II on the printing plate at the top of the raised portions. Letters I and I6, respectively, together with corresponding indented and raised portions, are female and male parts of rolls l3 and I4 for suitably forming dies.

A pair of thin metallic blanks I1 and Ilof the same general shape as plate III are superimposed on each other, as may be visualized from Fig. 2. The superimposed blanks I1 and I8 are passed through rolls I3 and I4 whereby each of the blanks are formed therein a series of characters corresponding to the characters on the rolls. The blanks, after having been passed through the rolls, maybe designated as dies or templates I9 and 2| corresponding respectively to blanks I1 and I8.

The raised and indented parts 22 and 23 of rolls I3 and I4 are of such size relative to each other that blanks I1 and I8 may be passed therebetween and the raised parts 22 will force the metal of the blanks into the indented parts 23, as may be visualized from Fig. 3. Letters I5 being formed inwardly with indented parts 23, when blanks are passed between the rolls the upper blank I1 is formed into die I9 with sharp letters |5a on top because of the direct contact of the blank with letters I5 of roll I3. Likewise, the letters |6 being formed outwardly of raised parts 22, the bottom blank I8 is formed into die 2| with sharp letters I6a on the underside thereof due to the direct contact of the blank with letters I6 of roll I4. Because the metal of blank I8 is pushed into the metal of blank I1, the abutting surfaces of the characters on the blanks as originally disposed are not so sharp as the letters on the top of die I9 and the letters on the bottom of die 2|.

In Fig. 4 there is shown the die I9 with the top surface uppermost and showing the sharp letters I5a on top of raised portions I9a. Only sufficient letters to show the formation are shown in perspective in this view. In Fig. 5 there is shown the die 2| with the bottom surface uppermost showing indented portions 2|a with the letters I Go sharply imprinted therein.

In Fig. 6 there is shown the arrangement of dies I9 and 2| and a thermoplastic blank 22 interposed therebetween. It will be noted that in this arrangement die I9 is below die member 2|. That is to say, die member I9 formed as a female die (Fig. 3) now becomes a male die. In this manner, when heat and pressure are applied to the assembled dies and thermoplastic blank, the material of the blank is forced into the female portions of die 2| by the male portions of die I9. The material of the thermoplastic blank is forced into contact with the sharp characters on the underside of die 2| by the sharp characters on the top surface of die I9.

In the process of forming dies I9 and 2|, the underside of the indentations in die 2| are somewhat smaller than the outside of the raised portions of die I9 inasmuch as these are forced one into the other. Therefore, when their posi-- tionis reversed, as in Fig. 6, and heat and pressure applied, the metal surfaces of the raised and indented portions fit closer to each other and therefore push the thermoplastic material into sharper formations. That is to say, there is a greater tendency for the metal to flow into every small crevice or space which exists. In this fashion, not only do the letters have sharp outlines, but their top surfaces which do the actual printing are sharp and even.

In Figs. 7, 8 and 9, a jig 25 for holding the dies and blank, and the apparatus 43 for applying pressure and heat thereto are shown.

Jig 25 includes an insulating handle 26 to which a base member 21 is attached by any well known means such as a bolt 28. Around the outside edge of base 21 there is a rim 29 forming a rectangular area 3| therein which is of suflicient size to receive dies I9 and 2| as well as thermoplastic blank 22. The die I9 is first placed in area 3| with blank 22 on top thereof, after which die 2| is placed on top of the blank. Overlying the top of die 2| is a member 32 having an indented or cut-out portion 33 corresponding to the area of the characters on die 2|. Member 32 is held to a suitable backing member 34, which in turn is attached to a strap 35 extending the full length. Studs 36 and 31 are arranged at the ends in order to align the fixture parts always in the same relative positions and a threaded stud 38 and nut 39 are arranged as shown to hold the parts assembled.

In Fig. 8 the parts of the fixture are shown as though the upper part, i. e. strap member 35, were pivoted around its forward end so as to have it lying out flat, and the dies and blanks are shown separated and in perspective in their proper relative positions. Thus the operating surfaces of all parts of the fixture are viewable. Blank 22 is shown formed into a printing plate.

When the dies and blanks are assembled into the fixture as shown, the space 33 receives the letters on top of the die 2| so that no direct pressure is exerted tending to fiatten the letters. After the assembly has been made, the fixture is inserted. between the members 4| and '42 of the press 43, which for example may be a hydraulic press. Members 4| and 42 may be heated in any suitable fashion, and as shown, an electric cord 44 is connected thereto for supplying heating current to the members 4| and 42. A cord 45 is provided for connecting the heater in member 4| with the heater in member 42. The fixture is left in the press for a suitable length of time to plasticize the thermoplastic material and to allow the pressure exerted to force the material to flow into the spaces provided by the die members.

Depending upon the type of material used, different pressures and temperatures may of course be used, as is well understood by those skilled in this art.

While particular embodiments of the invention have been shown, it will be understood, of course, that the invention is not limited thereto since many modifications may be made, and it is, therefore, contemplated by the appended claims to cover any such modifications as fall within the true spirit and scope of the invention.

The invention having thus been described,

what is claimed and desired to be secured by Letters Patent is:

1. The method of forming a flat plastic article comprising the steps of, forming a male die and a female die by placing a pair of thin metallic members together and applying pressure thereto with die members having male and female characters, reversing the relative position of said male die and said female die, placing a thermoplastic sheet between said reversed dies, and applying heat and pressure to the assembly.

2. The method of forming a flat plastic article comprising the steps of, assembling a pair of flat metallic members one on top of the other, imprinting said pair of members with a male and female character arrangement, reversing the position of said members after imprinting, placing a thermoplastic sheet between said reversed members, and applying heat and pressure thereto.

3. The method of forming a flat plastic article comprising the steps of, assembling a pair of flat metallic members one on top of the other, passing said assembled members between a pair of rolls having a male and female character arrangement thereon, reversing the position of said members after rolling. placing a thermoplastic sheet between said reversed members, and applying heat and pressure thereto.

4. The method of forming a flat plastic article comprising the steps of, assembling a pair of flat metallic members one on top of the other,

imprinting said pair of members with a male and female character arrangement, reversing the position of said members after imprinting, placing a sheet of thermoplastic material between said reversed members, applying heat and pressure thereto, and cooling and separating said reversed members.

THOMAS I. RESS.

REFERENCES CITED The following references are of record in the 

